ETYM French chance, Old Fren. cheance, from Late Lat. cadentia (a allusion to the falling of the dice), from Latin cadere to fall; akin to Skr. çad to fall, Latin cedere to yield, Eng. cede. Related to Cadence.
(Homonym: chants).
A risk involving danger.
Likelihood, or probability, of an event taking place, expressed as a fraction or percentage. For example, the chance that a tossed coin will land heads up is 50%.
As a science, it originated when the Chevalier de Méré consulted Blaise Pascal about how to reduce his gambling losses. In 1664, in correspondence with another mathematician, Pierre de Fermat, Pascal worked out the foundations of the theory of chance. This underlies the science of statistics.

To be the case by chance

To take a risk.

Unpremeditated killing of a human being in self defense.
1. Accidental homicide not entirely without fault of the killer but without evil intent
2. Haphazard action; confusion

1 archaic; casual
2. Full of chance or uncertainty